Searching the stars
Students in Jason Wright's SETI graduate course watch the sun set over Green Bank Observatory. Credit: Jason Wright, Penn State
Since before the dawn of history, humans have looked up at the sky in wonder. With the invention of the optical telescope in the early 1600s, we began our quest to bridge the heavens and the Earth. And all the while, we have wondered whether we are, in fact, alone in the universe.
The birth of radio astronomy, in the early 1930s, opened a new window on the cosmos. In 1959, the first scientific paper on SETI — the search for extraterrestrial intelligence — was published in Nature; and less than a year later, at the National Radio Astronomy Observatory in Green Bank, West Virginia, the field of SETI research was born.
But since the 1960s, funding battles have hindered SETI scientists' efforts to advance this research. In 1993, following a tumultuous congressional tug-of-war, federal funding for SETI was cut off entirely, and the field has since had to survive on sporadic private funding.
"Because the government doesn't fund SETI, our model for how we train scientists in this field is broken," says Jason Wright, an associate professor of astronomy and astrophysics at Penn State. "Almost no one's being trained to do this work. As a result, until recently there have been very few people with any training in SETI at all—and by 'very few' I mean a couple dozen in the world."
For his part, at least, Wright aims to remedy that. In the spring of 2018, he launched Penn State's first graduate-level course in SETI — one of only two in the country, and the only one that is part of an astrobiology Ph.D. program. The University's Astrobiology program is, itself, one of the only ones in the world. "By having a graduate course where we teach students SETI," Wright says, "we are significantly increasing the number of people with expertise in the field.”
Wright's efforts coincide with a significant shift in the SETI landscape. In July 2015, billionaire tech investor Yuri Milner and a number of prominent scientists, among them Frank Drake — the Cornell University astronomer who is regarded as the father of SETI — and the late luminary physicist Stephen Hawking, announced the largest and most comprehensive search to date: Milner's 10-year, $100 million Breakthrough Listen Initiative, established at the University of California, Berkeley, at the Berkeley SETI Research Center. In 2017, Wright took a sabbatical there, and some of the researchers he worked with agreed to participate as guest faculty in his soon-to-be-launched SETI course.
Success and serendipity
Wright invited his Berkeley colleagues to teleconference into one of his class sessions, where they talked to the students about the Breakthrough Listen Initiative and the science being done at Berkeley and Green Bank Observatory, and taught them some basics of radio astronomy. Culminating the course, Wright led a field trip to Green Bank, where his students worked with the Berkeley scientists to gather data with one of the largest and most powerful radio telescopes in the world — the 100-meter Green Bank Telescope.
"We partnered with the Breakthrough Listen lab to maximize the chances that the students' search would be a success," Wright says. "Ultimately, you hope to find a signal from extraterrestrial technology; but, of course, you have to go in assuming the chances are extremely small."
Historically, given these miniscule odds coupled with a stark lack of results, many have argued that SETI is a waste of time, money, and effort. As far back as 1961, Frank Drake, Carl Sagan, and others estimated the probable number of civilizations in the Milky Way Galaxy alone to be anywhere between a thousand and a million, and yet as of 2018 — nearly 60 years later — SETI has not confirmed a single instance of extraterrestrial intelligence. Knowing all this, why would anyone choose to sink valuable resources — even their very reputation — into such an endeavor?
The reasons, as Wright presents them, are complex — hinging on the interconnectedness of the subdisciplines within the field of astronomy, the broader benefits of technology development, and the inestimable magnitude of collateral discoveries.
"Look at the Drake Equation," he says, referring to Frank Drake's famous description of the factors involved in estimating the number of technological civilizations that may exist in our galaxy. "That equation alone is filled with all kinds of astronomy and astrobiology. In order to know what stars to look at, we have to know what stars might have planets. Discovering planets around other stars is one of the major achievements in astronomy in the past 30 years, and finding which ones could host life is a major goal of NASA.”
In fact, NASA spends billions of dollars a year on its astrobiology program, searching for passive extraterrestrial life — a mere half-step away from searching for active extraterrestrial intelligence. And the technology that's been developed toward detecting signals from other star systems has driven a number of incredible, serendipitous discoveries.
“Some of the most famous false positives in SETI have turned out to be extraordinarily interesting," Wright says. Take pulsars, for instance: When the first pulsar was discovered by Jocelyn Bell and Antony Hewish in 1967, they somewhat facetiously named it LGM-1 — "little green men” — because no one then expected to see regular radio pulses coming from the sky. Hewish was awarded the Nobel Prize in Physics for that discovery, and Bell eventually received the $3 million Breakthrough Prize.
The subsequent discovery of a second type of pulsar also won a Nobel Prize; and the discoveries of quasars and active galactic nuclei hold similar stories — albeit without the Nobel Prizes. “Because SETI is part of — is embedded within — these larger fields, and because it's interested in extraordinary anomalies,” Wright explains, “it can't help but be part of broader astronomical discovery."
So, despite the admittedly long odds, Wright's students worked diligently to prepare a novel observation program, laying the groundwork for a potential breakthrough of their own. “This is a graduate-level class,” Wright says, “so you don't just learn about things; you learn to do them. The students decided what would be the best things to look at, the observing strategy, the frequencies they would use. They wrote the observing scripts, and they would eventually become radio astronomers by actually using the telescope.”
Green Bank
With all the pieces finally in place, Wright recalls, "we piled into a van and drove down to Green Bank,” in the National Radio Quiet Zone — a roughly 13,000-square-mile area where radio transmissions are highly restricted in order to minimize interference. Within 10 miles of the telescopes at Green Bank, he explains, "you're not allowed to have anything that generates radio waves."
Not only is Green Bank one of the world's premier radio astronomy observatories — hosting the largest fully steerable radio telescope on the planet, the 100-meter Robert C. Byrd Green Bank Telescope (known affectionately as the GBT) — but it is, in fact, home to the oldest radio telescopes in the world, including those first used to detect astronomical radio sources. In addition to the GBT, Green Bank hosts six other radio telescopes, ranging in diameter from 13.7 meters to 43 meters; posing with them, Wright and his students managed to capture a few mementos, even though, to avoid creating cell phone interference, they had to rely on a disposable film camera.
Jason Wright and students in his SETI graduate course, at Green Bank Observatory in Green Bank, West Virginia. Credit: Jason Wright, Penn State
Entering the control room — a giant Faraday cage that shields the equipment's radiation from the telescopes — and finally meeting one of the Berkeley astronomers in person, the group was ready to conduct their search. For six hours, they listened with the mammoth Green Bank Telescope for the faintest of radio signals from faraway space, focusing on a small window of the radio spectrum known as the Water Hole, where there is relatively little background noise. "If you're listening for a weak signal,” Wright explains, “that's the best place to look."
"The experience was amazing," says Sofia Sheikh, a Ph.D. candidate in astronomy and astrophysics at Penn State. "I've used the Green Bank Telescope before, remotely; but being there in person was an entirely different experience. Being able to talk with the operators in person; to be in the control room in front of the giant screens; to hit 'go' and watch that behemoth of a telescope, the size of two football fields, start to slowly change position — it was incredible."
Sheikh plans to use the data she and her peers collected at Green Bank in her graduate thesis, which she says "will, as far as I know, be the first astronomical SETI thesis written by a woman." And, as the students' survey was the first of its kind, there is also the possibility of producing a peer-reviewed publication.
"I would love to see a paper come out of this work," Sheikh says. "That would be an awesome memorial to Penn State's first SETI course."
The PSETI Center
Well ahead of the trip to Green Bank, Wright and colleagues at Penn State had been putting their heads together — thinking about different and unique implementations of SETI, devising new and novel search strategies to look for signals beyond the radio spectrum, and shaping the University's curriculum to reflect those evolving methodologies. Getting the SETI course off the ground was a critical step; and after just one semester as a special topics offering, it was officially added to the curriculum.
Concurrently, Wright and his colleagues had developed a plan for a SETI research center — one that would support both Penn State researchers and the global community of SETI scientists. Working with the University's development officers, former SETI Institute chair John Gertz, and even Penn State President Eric Barron, they began a major fundraising campaign to endow the PSETI Center at University Park.
“Penn State has all the pieces to do a really good job at giving the search for extraterrestrial intelligence an academic home,” Wright explains. "We have one of the only astrobiology programs in the world. We actually do SETI here and we publish SETI papers, which makes us a major player in the field. We're a big research university. And, of course, we have the curriculum now. I can't think of any other place that has all of those pieces."
Although Wright and his colleague Steinn Sigurdsson are the only two Penn State faculty members with SETI as a significant part of their research portfolio, a large number of others will broaden the Center's expertise: Evan Pugh Professor Alex Wolszczan, who co-discovered the first exoplanets, and colleagues from Penn State's Center for Exoplanets and Habitable Worlds will join researchers from the Astrobiology Research Center, the Center for Astrostatistics, and the Institute for Gravitation and the Cosmos — as well as scientists worldwide who are sharing data through the University's globe-spanning Astrophysical Multimessenger Observatory Network (AMON).
“We've got everything," Wright reckons. "If you're going to look for extraterrestrial intelligence, this is what you need — and we’re right at the center of it.”
A further sign of Penn State's worthiness as a global SETI hub, scientific giants Frank Drake, Freeman Dyson, and Nobel Laureate George Smoot sit on the PSETI Center's advisory board, as do former NASA Kepler Mission Scientist Natalie Batalha, NASA Innovative and Advanced Concepts group adviser David Brin, prominent Caltech astronomy professor Andrew Howard, and Thirty Meter Telescope IRIS Project Scientist Shelley Wright.
“I'm really proud of what we’re doing here,” Wright says, smiling widely. “This is something the University is really serious about pursuing long-term — and we're just as serious about making sure the whole SETI community benefits. I think that's why so many leaders of the field have signed on to endorse this project — they see the value this will have to the entire scientific community.”
Taking the long view, venturing boldly into new frontiers, Wright and his colleagues are poised to advance both their field and humanity’s understanding of its place in the universe. In time, they may find like minds — out there, ready to join them.